title: Evaluation of facial attractiveness for patients with malocclusion: a machine-learning technique employing Procrustes.
abstract: OBJECTIVE
  To establish an objective method for evaluating facial attractiveness from a set of orthodontic photographs.
  
  
  METHODS
  One hundred eight malocclusion patients randomly selected from six universities in China were randomly divided into nine groups, with each group containing an equal number of patients with Class I, II, and III malocclusions. Sixty-nine expert Chinese orthodontists ranked photographs of the patients (frontal, lateral, and frontal smiling photos) before and after orthodontic treatment from "most attractive" to "least attractive" in each group. A weighted mean ranking was then calculated for each patient, based on which a three-point scale was created. Procrustes superimposition was conducted on 101 landmarks identified on the photographs. A support vector regression (SVR) function was set up according to the coordinate values of identified landmarks of each photographic set and its corresponding grading. Its predictive ability was tested for each group in turn.
  
  
  RESULTS
  The average coincidence rate obtained for comparisons of the subjective ratings with the SVR evaluation was 71.8% according to 18 verification tests.
  
  
  CONCLUSIONS
  Geometric morphometrics combined with SVR may be a prospective method for objective comprehensive evaluation of facial attractiveness in the near future.
authors.affiliation: a  PhD Student, Department of Orthodontics, Peking University School and Hospital of Stomatology, Haidian District, Beijing, China.
authors.forename: Xiaonan
authors.initials: X
authors.lastname: Yu
authors.forename: Bin
authors.initials: B
authors.lastname: Liu
authors.forename: Yuru
authors.initials: Y
authors.lastname: Pei
authors.forename: Tianmin
authors.initials: T
authors.lastname: Xu
mesh_terms: D000293:Adolescent; D000328:Adult; D059925:Anatomic Landmarks / Q000033:anatomy & histology; D001185:Artificial Intelligence; D001504:Beauty; D002508:Cephalometry / Q000379:methods; D002648:Child; D002681:China; D005145:Face / Q000033:anatomy & histology*; D005260:Female; D006801:Humans; D008297:Male; D008310:Malocclusion / Q000523:psychology* / Q000628:therapy; D008311:Malocclusion, Angle Class I / Q000523:psychology / Q000628:therapy; D008312:Malocclusion, Angle Class II / Q000523:psychology / Q000628:therapy; D008313:Malocclusion, Angle Class III / Q000523:psychology / Q000628:therapy; D016571:Neural Networks, Computer; D010781:Photography; D012904:Smiling; D012984:Software; D055815:Young Adult